bin/57630: lptcontrol gives "device busy" if device turned off

[Bruce Evans]

On Mon, 6 Oct 2003, Klaus-J.Wolf wrote:

> >Description:
> "lptcontrol -ei -d /dev/lpt0" during boot time fails with "device busy"
> if the printer is turned off at that time.

lptcontrol should be run on the control device (not /dev/lptN).

Support for using the control device automatically was broken in
rev.1.8 of lptcontrol.c.

Existence of the documented control device was broken in FreeBSD-5
as part of devfs lossage.  The documented control device is "/dev/lpctlN"
(see lptcontrol(8), but devfs creates "/dev/lptN.ctl".

The lpt driver also has support for control bits in the minor number.
(The control device is a special case of this -- it uses bit 0x80.)
There are 6 control bits, giving a total of 64 possible devices per
unit.  devfs only creates 2 of these.

Bruce